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73 lines
3.5 KiB
SQL
73 lines
3.5 KiB
SQL
-- { echo }
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set allow_experimental_window_functions = 1;
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-- just something basic
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select number, count() over (partition by intDiv(number, 3) order by number) from numbers(10);
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-- proper calculation across blocks
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select number, max(number) over (partition by intDiv(number, 3) order by number desc) from numbers(10) settings max_block_size = 2;
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-- not a window function
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select number, abs(number) over (partition by toString(intDiv(number, 3))) from numbers(10); -- { serverError 63 }
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-- no partition by
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select number, avg(number) over (order by number) from numbers(10);
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-- no order by
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select number, quantileExact(number) over (partition by intDiv(number, 3)) from numbers(10);
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-- can add an alias after window spec
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select number, quantileExact(number) over (partition by intDiv(number, 3)) q from numbers(10);
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-- can't reference it yet -- the window functions are calculated at the
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-- last stage of select, after all other functions.
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select q * 10, quantileExact(number) over (partition by intDiv(number, 3)) q from numbers(10); -- { serverError 47 }
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-- must work in WHERE if you wrap it in a subquery
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select * from (select count(*) over () c from numbers(3)) where c > 0;
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-- should work in ORDER BY
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select number, max(number) over (partition by intDiv(number, 3) order by number desc) m from numbers(10) order by m desc, number;
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-- also works in ORDER BY if you wrap it in a subquery
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select * from (select count(*) over () c from numbers(3)) order by c;
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-- Example with window function only in ORDER BY. Here we make a rank of all
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-- numbers sorted descending, and then sort by this rank descending, and must get
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-- the ascending order.
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select * from (select * from numbers(5) order by rand()) order by count() over (order by number desc) desc;
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-- Aggregate functions as window function arguments. This query is semantically
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-- the same as the above one, only we replace `number` with
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-- `any(number) group by number` and so on.
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select * from (select * from numbers(5) order by rand()) group by number order by sum(any(number) + 1) over (order by min(number) desc) desc;
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-- different windows
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-- an explain test would also be helpful, but it's too immature now and I don't
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-- want to change reference all the time
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select number, max(number) over (partition by intDiv(number, 3) order by number desc), count(number) over (partition by intDiv(number, 5) order by number) as m from numbers(31) order by number settings max_block_size = 2;
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-- two functions over the same window
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-- an explain test would also be helpful, but it's too immature now and I don't
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-- want to change reference all the time
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select number, max(number) over (partition by intDiv(number, 3) order by number desc), count(number) over (partition by intDiv(number, 3) order by number desc) as m from numbers(7) order by number settings max_block_size = 2;
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-- check that we can work with constant columns
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select median(x) over (partition by x) from (select 1 x);
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-- an empty window definition is valid as well
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select groupArray(number) over () from numbers(3);
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-- This one tests we properly process the window function arguments.
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-- Seen errors like 'column `1` not found' from count(1).
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select count(1) over (), max(number + 1) over () from numbers(3);
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-- Should work in DISTINCT
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select distinct sum(0) over () from numbers(2);
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select distinct any(number) over () from numbers(2);
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-- Various kinds of aliases are properly substituted into various parts of window
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-- function definition.
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with number + 1 as x select intDiv(number, 3) as y, sum(x + y) over (partition by y order by x) from numbers(7);
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